Since noone has mentioned it in the post yet those Hybrid antler horns are something you might want to try for a tough chew vs. animal product.
They cant splinter (like real a horn) are long-lasting and safe for pups too. Come in a variety of sizes. Only real downside I have Found is... they seem to get Lost easily. lol. I'm sure those "missing" ones will turn up someday.
Nowdays a lot of the animal-based chews are coming from China or other areas outside the USA. No telling how they are processed and we try make it a rule to avoid the imported chews or toys.